Socket for tube-type incandescent lamps



Sept. 7, 1954 R. P. ROSEN SOCKET FOR TUBE-TYPE INCANDESCENT LAMPS Filed June 13, 1952 INVENTOR. en; RUBEN P- Rosen l Il Il iii@ BWM!

F1 TTOR/l/EV Patented Sept. 7, 1954 SCKET FOR TUBE-TYPE INCANDESCENT LAMPS Ruben P. Rosen, Philadelphia, Pa., assigner to Progress Manufacturing Company, Inc., Philadelphia, Pa., a corporation of Pennsylvania Application J une 13, 1952, Serial No. 293,415

6 Claims.

This invention relates generally to electrical lamp sockets and is more particularly concerned. with an improved construction of an electrical socket designed to operatively receive the end of a tube type incandescent lamp.

Among the principal objects of the present invention is to provide a lainpholder or socket for the end of a tube type incandescent lamp, the socket being made of a pair of parts of of Figure 1, parts being broken away to expose others;

Figure 8 is an enlarged elevational view on line 3 3 of Figure 2; and

Figure 9 is an enlarged elevational view on line e-S of Figure 2.

This invention constitutes an improvement to the lampholder or socket which is the subject of United States Letters Patent 2,554,541, issued which one is fixed in position and the other is i to the applicant herein on May 29, 1951, and shiftable relative thereto for mounting and disreference mei be had to the aforementioned mounting the lamp, contact elements being patent for the description and operation of all carried by the aforementioned parts for open- Ports not Specifically described herein. ing and closing the circuit to the lamp switch Referring noW more Particularly to the drowas the lamp js mounted and dismounted, and ings, it Will be ObSelVed that the l'lilphOlde O the contact element carried by the fixed one of the present invention iS adapted OI use in a the aforementioned parts being normally fixed lighting Xtul'e es SnoWn in Figure 1, Said lightin position relative thereto ing xture having a main supporting base I0 Still another object of the present invention designed for use in oonjunotion With e' tube-type is to provide such a socket wherein the contact ineendeeeent lamp i the opposite endS of which element carried by the fixed one of the socket ene TeSDeCtiVeiy received by e Deir of aXielly parts is spring pressed for movement only to S13-toed Sooket Darts l2 and i3, the Socket Part take up wear. l2 being immovably xed in position upon the Other objects and advantages of the present Supporting bese it of the lighting fixture, While invention Win appear more fuiiy hereinafter, the socket part I3 constitutes a relatively movit being understood that the present invention consists substantially in the combination, construction, location and relative arrangement of parts, all as described in detail hereinafter, as

shown in the accompanying drawings and as Y nally pointed out in the appended claims.

In the accompanying drawings, which are illustrative of a preferred form of the present invention:

able element of a lampholder assembly designated generally I, constructed in accordance with and embodying the principles of the present invention.

The relatively xed socket part I2 essentially includes a main body part I5 provided with a socket l5 adapted to receive the upper end of the tubular lamp II. It will be understood that the socket part I2 is fixed to the mounting base Figure l is a perspective View of a tube type lll of the xture with the axis of its socket I6 incandescent lamp carried by vertically spaced extending lengthwise of the xture, that is, colamp sockets of a lighting xture, the present incident with the axis of the tube lamp adapted invention being incorporated in the lowermost to be supported between the oppositely disposed lamp socket; sockets I2 and I3.

Figure 2 is a side elevational view of the lower- 40 The lampholder I4, of which the socket part most lamp socket shown in Figure 1, the xed and shiftable socket parts being shown disassembled;

Figure 3 is an exploded view showing in perspective the component parts of the lowermost lamp socket;

Figure 4 is a plan section on line 4 4 of Figure 5;

Figure 5 is a sectional elevation of the lowermost lamp socket, which is shown without the lamp mounted therein;

Figure 6 is an enlarged sectional elevation on line 6-6 of Figure 8;

Figure 7 is a side elevational view on line 'I-1 I3 forms a component element, includes a supporting back plate I7 adapted to be xedly secured to the supporting base I0 of the lighting xture by a pair of screws I8--I8 projected through openings Iii- I9 formed in the base Ill and into threaded apertures 20-20 formed in the supporting back I'I. This supporting back is provided along its opposite edges with channel-shaped guideways 2I-2I and at its top with a horizontally disposed plate 22 terminating in a vertically disposed flange 23. The horizontally disposed top plate 22 is provided with a pair of laterally spaced struck out portions forming a pair of spring suspension hooks 2li-24 from which are respectively suspended a pair of coiled tension springs -25.

The socket part I3 is slidably associated with the supporting back plate I1 and is provided with a generally circular part 21 which is centrally recessed to provide a socket 28 for receiving the lower end of the tubular lamp II, and with an integrally formed rear part 29 adapted to be slidably received within the channeled supporting back I1. It will be noted that the rear part 29 is generally of rectangular form, the opposite longitudinal edges 3-30, being respectively adapted for sliding, t within the channels 2I-2I of the fixed member I1.

Extending across the bottom end of the guided rear part 2S is a plate 3l having a pair of laterally spaced hooks 32-32 formed thereon, these hooks being extended upwardly through suitable openings 33-33 formed in the bottom end of the part 29 for respective engagement by the lower ends of the coiled extension springs 25-25.

Whereas the relatively xed socket part I2 is internally fitted with an unswitched contact element (not shown) for electrically connecting the inserted end of the tubular lamp to a conductor (not shown) immediately upon insertion of the lamp end into the socket I3, the movable socket part I3 of the lamp holder assembly I4 is internally provided with a rotatable fixture switch as well as with an interlock switch which is operative to open the circuit to the lamp when the socket part I3 is retracted into lamp removing position. Thus, referring more particularly to Figures 3 and 5, it will be noted that the base of the socketed part 21 is centrally bored, as at 34, to receive a rotatable switch knob 35, the inner end of which is kerfed, as at 35, to receive an S-shaped contact element 31. The opposite ends of this rotatable contact element 31 are respectively adapted to engage the arcuately shaped portions 38-38 of a pair of contact members 39 and 4I) xed in the base of the socket 23, the member 40 being provided with a wing element 4l the free end of which is adapted to project upwardly through an opening 42 formed in an insulating plate 43 overlying the elements 39 and 49. The arcuately shaped parts 38-38 of these fixed contact elements 39 and 4D are disposed in diametrically opposed relation within a suitable well 44 formed in the base of the socket 28. A metal contact plate 45 overlies the insulating plate 43 and is in electrical contact with the wing element 4I projecting upwardly through the opening 42 in the intervening insulating plate 43. The plate 45 is centrally provided with a raised portion 46 adapted for contact by the metal cap (not shown) fitted on the end of the tube lamp. The several parts 35, 31, 39, 40, 43 and 45 are all secured in their xed relation, as shown, within the base of the socket 28 by suitable securing elements, such as pins 41-41 driven into the part 21 through suitably registering apertures in the members 43 and 45.

The member 39 is provided with a lateral extension 43 projected through an opening 49 formed in the back Wall portion of the socket 28. The extension 48 terminates in an upturned lip 48a which is disposed with its outer surface flush with the back surface of the circular part 21, and which is of such size and shape as to fit snugly into the opening 49, being thus adapted to wipingly engage and make electrical contact with a main or button contact element 50 carried by a contact mounting xedly secured to the channeled support I1.

The button contact element 50 forms a component part of the aforementioned contact mounting, which also includes a base member 5I molded or otherwise formed of insulating material. The latter is made with a plate 5IEL which is generally triangular in shape, and integrally formed therewith are a pair of opposed longitudinally extending walls 52-52 joined together at one end by a transverse wall 53. 'Ihe ends of the walls 52-52 remote from the wall 53 are arranged to slidably retain therebetween the main or button contact element 5U, which is in the form of a cylindrical member provided with a rounded nose 54 normally positioned to project beyond the walls 52-52, the nose 54 being of such size and shape as to form a cylindrical shoulder 55 at the base thereof. Disposed between the walls 52-52 is a secondary contact element 56 having a portion thereof remote from wall 53 pressed flat against the triangular plate 5I, and having a portion thereof proximate the wall 53 curved to position it out of contact with the triangular plate 5I. The contact element 50 is provided with a central bore 51 through a major portion thereof and a coil spring 58 is disposed therein to react between the contact element 50 and the fiat end of the contact element 56. The contact member 50 is shifted axially by the action of coil spring 58, but such shifting movement is limited by a pair of opposed inwardly projecting shoulders 59-59 formed respectively on walls 52-52 for coaction with the shoulder 55 on the contact element 59. The triangular plate 5Ia is xedly secured to the channeled support I1 by fastening elements 60 projected through openings I in the three corner portions thereof and registering openings 62 in the support I1. The contact member 56 is connected, as by soldering or welding to the terminal end of an insulated conductor wire 63.

When the tubular lamp I I is mounted in position, as shown in Figure 1, the contact element 39 is in electrical engagement with the contact element 50 (as seen Figure '7), and in this condition of the parts the lamp may be turned on and oi by rotation of the rotary switch element 31.

Upon axially shifting the socketed part I3 of the lamp holder I4 into its lamp removing position, lip 48@L of the contact element 39 moves to a position below the relatively xed contact element 50 in consequence of which the connection to the lamp is broken. If desired, and it is generally preferable so to do, the contact element 5D is so arranged with respect to the lip 48, the latter being movable with the socketed part of the lampholder I4, as to provide for breaking of the circuit to the contact element 39 when the socketed part is completely free of its lamp and is thus in its uppermost position. In such case, the lip 48a of the contact element 39 would be spaced above the contact element 59, engagement with the latter being then normally made only when the socketed part of the lampholder I4 is in lamp supporting position, as shown in Figure 7.

In assembling the lamp holder I4, contact element 5D is pressed axially inward, the coil spring 58 being thus compressed and the shoulder 55 of the contact element 5U being thus disposed in spaced relation to the pair of shoulders 59--59 formed on the longitudinally extending walls 52-52. As the lip 48a and the contact element 50 wear 'due to repeated relative movement therebetween, the action of the coil spring 58 causes the contact element 50 to axially shift in order to take up the same. Otherwise it will be noted,

there is no appreciable shifting movement of the contact element 5U, either when the lamp Il is placed in the lampholder or when it is removed therefrom.

It will be understood, of course, that the present invention is susceptible of various changes and modifications which may be made from time to time without involving any departure from the general principles or real spirit thereof, and it is accordingly intended to claim the same broadly, as well as specifically, as indicated in the appended claims.

What is claimed as new and useful is:

1. In a contact mounting for use in a safety interlock switch having a pair of relatively shiftable parts, a base member formed of insulating material and comprising a plate adapted to be rigidly secured to one of said Darts, and a pair of Walls integral with and extending outwardly from said plate in relatively spaced relation, opposed portions of said walls being provided with proximate surfaces adapted to engage the opposite sides of an elongated member extending outwardly from said plate, an elongated main contact element between the proximate surfaces of said opposed wall portions and in spaced relation to said plate, said contact element being axially shiftable and the end portion of said main contact element remote from said plate being fully exposed, elongated terminal means between said pair of walls and extending along said plate between the same and said main contact element, a coil spring between the latter and said terminal means acting to press one end portion of said terminal means against said plate and to axially shift said main contact element, and means for limiting said axial shifting of the main contact element, the opposite end portion of said terminal means being laterally spaced relative to said coil spring and main contact element and having means adapted for connection to a contact wire.

2. In a contact mounting for use in a safety interlock switch having a pair of relatively shiftable parts, a base member formed of insulating material and comprising a plate adapted to be rigidly secured to one of said parts, a pair of walls integral with said plate and disposed in relatively spaced relation, opposed portions of said walls being provided with proximate surfaces adapted to engage the opposite sides 0f an elongated member angularly disposed relative to said plate, and a pair of shoulders respectively integral with said walls and disposed in opposed relation to one another and in spaced relation to said plate, an elongated main contact element between the proximate surfaces of said opposed wall portions and in spaced relation to said plate, said main contact element being axially shiftable, a shoulder intermediate the ends of said main contact member, elongated terminal means between said pair of walls and extending along said plate between the same and said main contact element, and a coil spring between the latter and said terminal means acting to press one end portion of said terminal means against said plate and to axially shift said main contact element to a position wherein said shoulder intermediate the ends of the latter abuts said inwardly projecting shoulders of said pair of walls, in which position the end portion of said main contact element remote from said plate is fully exposed, the opposite end portion of said terminal means being laterally spaced relative to said coil spring and main contact element and having means adapted for connection to a contact wire.

6. 3. In a contact mounting for use in a safety interlock switch having a pair of relatively shiftable parts, va base member formed of insulating material and comprising a plate adapted to be rigidly secured to one of said parts, and a pair of walls integral `with said plate Vand disposed in relatively spaced relation, opposed portions of said walls being respectively vprovided with proximate surfaces adapted to engage diametrically opposed side portions of a cylindrical member disposed normally relative to said plate, and also being respectively provided with opposed inwardly projecting shoulders, a cylindrical main contact element between the proximate surfaces of said opposed wall portions and in spaced relation to said plate, said main contact element being axially shiftable and having a circumferential shoulder formed intermediate its ends, flat elongated means between said lpairs of walls and extending atwise along said plate between the same and said main contact element, and a -coil spring between the latter and said terminal means and eoaxially related to said main contact element, said coil spring acting to press one end portion of said terminal means against said plate and to axially shift said main contact element to a position wherein said circumferential shoulder of the latter abuts said inwardly projecting shoulders of said pair of walls, in which position the end portion of said main contact element remote from said plate is fully exposed, the opposite end portion of said terminal means being laterally spaced relative to said coil spring and main contact element and having means adapted for connection to a contact wire.

4. In a contact mounting for use in a safety interlock switch having a pair of relatively shiftable parts, a base member formed of insulating material and comprising a plate adapted to be rigidly secured to one of said parts, a main contact element carried by said plate and disposed in spaced relation thereto, elongated terminal means extending along said plate between the same and said main contact element yieldable means between the latter and said terminal means acting to press one end portion of said terminal means against said plate and to axially shift said main contact element away from said plate for fully exposing one end thereof, and means for limiting said axial shifting of the main contact element, the opposite end portion of said terminal means being laterally spaced relative to said yieldable means and main contact element and being adapted for connection to a contact wire.

5. In a contact mounting for use in a safety interlock switch having a pair of relatively shiftable parts, a base member formed of insulating material and comprising a plate adapted to be rigidly secured to one of said parts, and a pair of walls integral with and extending outwardly from said plate in relatively spaced relation, opposed portions of said walls being provided with proximate surfaces adapted to embrace the opposite sides of a contact member extending outwardly from said plate, a main contact element having an outer portion thereof disposed between the proximate surfaces of said opposed wall portions and in spaced relation to said plate, said outer portion of the contact element being shiftable relatively to said socket and having an extremity which projects freely from said socket and is normally fully exposed, elongated terminal means between said pair of walls and extending along said plate between the same and said main contactelement, said contact element being normally spring biased to effect yielding engagement of its outer extremity with a contact carried by the other of said relatively shiftable parts, said plate having an opening therein in communication with the space between the walls thereof, and a conductor wire projected through said opening and electrically connected to said terminal means.

6. In a contact mounting for use in a safety interlock switch having a pair of relatively shiftable parts, a base member formed of insulating material and comprising a plate adapted to be rigidly secured to one of said parts, said plate having an elongated socket presenting away from the part to which said base is secured and toward the other of said relatively shiftable parts, a contact element yieldably disposed in said socket with its outei` end projecting externally of said socket for yieldable contacting engagement with a contact carried by said other relatively shiftable part, said contact element being constrained by the socket in which it is disposed against movement other than toward and awaxr from said base, said yieldably disposed contact element having terminal means extending therefrom along the bottom Wall of said socket and overlying an opening in said bottom wall of the socket, and a conductor projected into said socket through said bottom wall opening thereof and electrically connected to said terminal means.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,100,949 BriggsI June 23, 1914 2,554,541 Rosen May 29, 1951 FOREIGN PATENTS Number Country Date 145,543 Switzerland May 16, 1931 

